High-tension spark-plug.



J. & W. SHARP.

MGH TENSION SPARK PLUG.

Arrmoulon FILED DBo.9,19os.

Patented Oct. 5, 1909.

.Iori-ir' SHARP Aivii WILLIAM sir-IAR?, cs cLEvELAN'D, omo.

vSpecification o f Letterlatent.

HIGH-TENSION SPARK-PLUG.

Application-tiled December 9,- 1908. Serial No.' 466,648.

To-all whom it may concerm" Be it known that we, JOHN 'SHARP and WILLIAMSHARP,l citizens of the United Sta-tes,v and residents -of Cleveland,-in the. Ycounty of Cuyahoga and State of Ohio, have invented `vcertainnew and 'useful Improve. ments. in- High-Tension ySpark-Plugs, of whichwe hereby declare the following to be a enable others skilled in theartto which it appertains to make and use-the same.

Tliefobjects of the invention are to provide an improved form ofsparking plug,

eiiciene'y will be' obtained spark underall conditions of oul gas and:carbon producing vapors when exploded in the expansion chamber of-'theengine.

The sparking fplu hereinafter described is adapted to be sel low toprovide for admission of rarefied gas behind -the sparkingter'minals, to-enrich the spark and' to prevent it from blowing out and also toprovide chambers which will contain abody of vgas whichvwhen ignited bythe spark willv shoot out, into `the body of gasin the cylinder, andinsure its immediate explosion.

A further object obtained by theiiiternal chambers is found lin theopportunity thus afforded for 'heating the insulation of the innerterminal and its st m, and thus evaporating the moisture w ich oftenaccumulates therein, especially when the'insulation is composed oflaminated sheets, compressed together.

Further objectsof the invention are to provide protected terminals,which can not be bent or forced out of adjustment by rough usage and atthe same time are capable of easy adjustment.

A further advantage is found in a' hollow 'stein for the insulatedcentral terminal, by means of which and the. concentric form of theouter or ground terminal gasolene or other priming iuid can be directlyinjectedA into the body .of the sparking plug and if necessary into thecombustion chamber of the engine, thus simplifying the matter ofstarting the pist-on in a cold engine.

`A further advantage found in the opportunity afforded for heating thespark plug, is'

the fatter spark obtained, since the arc will be stronger when passingthrough a heated medium.. For this reason' also' less battery Cleansing,and is hol power will berequired to create a spark of predeterminedvolume.

.- The invent-ion further comprises the forms of 'construction l andcombination 'and ar'- range'mentof parts and provides vfor the variousrequirements hereinafter: described,

shown in Athe accompanying drawings, and

'specifically pointed out in the claims. full, clear, andeXactdescription, 'such as will In the accompanying drawings, Figure 1is Van elevation of the improvedfsparking plug; Fig. 2 is a-centrallongitudinal'section 4therethrough;'Fig. 3 is an elevation oftheinsulated or central-terminal and its stein; for -use in the explosionend of4 a gasolene i or other explosion engine, whereby increased ireducing a Fig. 4 isa similar view of the saine showe;` jing-a modifiedform of terminal heador ti provided with spiral' openings; nFig. 5 isafp'laiil view of the tip shown in Fig. 3 ;Fig. 6

lisl a plan view ofthe -tip shown'in Fig. 4; Fig.

7 is a longitudinalsection of an expansion chamber at the outer end ofthe insulated stem of theinner terminal adording an iiicreaseds'upplyofraretied gas, and Figs. 8,

-9 and 10- are'modiieid forms of the exterior or ground terminal adaptedto be attached to' the body ofthe plug. Fig-11` is a vertical lsection'of theV outer end of the stem showing a. valve therefor.

It may be prefaced that Asince this plug is adapted for use with.analternating and high tension current, theterminals are calledpositive or negative or ground merely for convenience in description.

'In these figures A is the metal body of lthe plug, screw threaded at Bfor` attachment to the explosion end of the engine cylinder.

This body is hollow and provided with a shoulder C against whichtheenlargement D formed in the cylindrical'insulation E of the centralmetal stein F rests. p acking nut G threaded' for` adjustment in thethreaded upper endf of the bodyA, clamps 'the parts securely together.The lower-portionl of the insulation E is tapered at H, and the walls ofthe hollow body A. are spaced therefrom so as to form -a' chamber withinthe body. A metallic conical head or tip J terminates the inner end ofthe stein F and this is shown to be provided with slits K, K, whichcommunicate with a central opening or chamber L in the tip, and thestein v`F is also hollow at M, therefore providing for an elongatedchamber extending throughout the stein, and preferably closed by aremovable screw plug N or valve N at its upper extremity. The stein Fand tip .l are preferably Psr'ewedl'together at 'O'in sucha man-.circular andv preferably conntersiink'atfsfo ner .as to provide.aclamping shoulder P asA `to Yprovide anouter rimoredgegtoward .againstwhich theinsulaton rests,.which is which oil'will run and thus prevent"it from sleeved over 4the" stem. The upper' endv of interfering withthe free'action of the'spark the stem is .shown to be externally screwbetween'the terminals. .These terminals may 7othreaded to receive themetallic clamping be made in several orms as shown, in'Fig's. 8, 'i'sleeves and nuts Q, R, and' S. The ip J. is 9 and '10"when" slittedacross the central tapeedltoward lower end and -ha's a opening as shownat'Fig. 8. A further ad terminal 'orifice `T through whichprojectsvantage is obtained in thatthe spark .will

the terminal wire U which tits tightly there.A "travel or revolve Afromone of the segmental "75 inbutcan,beforced outward orinward by tips" toanother and thus save, the terminal hand or by means of a toolinserted-in the from disintegration.` hollow 'stem M. It must be heldsecurely by. In Fig. 10 a. small nipple w', is shown friction so that inuse no sudden jar. will screwed into the semi-globulartip.'v In 1 5atfect it, but-be capable of manual ad` 9 the semi-globular tip isscrewed upon the 80j justment. tapered extremit Small changes as'thes'eIn'tlie form of tip shown in Fig, .3 the Sides are included wituln the'spirit of .the inof the'tip, :will have sulicient springacton toVI110I-1 *hold itfiniplacefflhe inner extremit of the fllavlng describedthe mventionwwhatwe Zo'metallic body 's .hollow'and spaced om the claimas newand desire to securelby-:Letters 85 metallicfinnertipto form achamber Vand Patent 1S1 Y l. the body rninates in a hemisphericalout-er' V l; In .COmblnationnin a spark plug',l a-Tholf terminal ,Wwhichis provided with a cenlOW Inet-al bOdy v] O )I'1 0I'1,l Sclfw'thl'dedir;

tralv orifice X, through which the inner inSeItlOIl into an englnecyl1nder,.a-apered terminal' wir@ yU projects, and standsflush mnerextremity therefor, .provided -wt l1 a z9d 4,with the outer terminal.The outer terminal chamber, and aSemi-globular termina1therevXis,providedlwithjine longitudinal slits Y, fOr pIOJeGtilg beyond saidtaperedextrem-v .,-llwvhich-serveto.admit gas in a wiredrawn 1ty,'thesald termmal provided with affcencoriditil .to .fthe-chamber V, where itex-V tralcountersunkorifice andwith ine'longipands and-.becpmes morerareied and hence tudmal shts, communicating .saids more explosive thanthe gas in the engine lchambe r,'an d an inneriterminal s aidce'nf.cylindenu'A second rarefa'ction takes place tral or1fce,`-acentral stemconnectediw'ith as thegasesv pass through the ne slits K, K saidinner terminal, land an ins `1 1l2 ition'tl1`ere `.v 1. ntothechamberformed within the hollow or,said.stem1and nsulationsecuredwithn. stem.The gases included within the cham said hollowbody'p* il -bers V and Mexplodeinstantaneously when 2. Ina Spark plug, in conrbinatiomaaholf thespark occurs, and are driven tlaming .low metal body, a projectingconicalrextrem-f violentlylinto the expansion chamber of the ity forsaid body containing'f'a gas chamber,' engine, thus vpreventing anypossibility of .and a rounded terminal therefor, Vsaid termi- 40: thefailurefof an explosion in the cylinder.; Anal provided with a centraloricefand 'withfzlQ-B# The slits/'communicate with the central narrowlongitudinal slits, communicating orii'ce, hence forming openings largeenough with said chamber', a hollow stem-therein-, a f topass thaflamaThe inner portion Z of metal tip therefor containing anfinner'cliamthebody'. of the plug is externally tapered ber, and alsol having narrowslitsin-its walls, nd'l'fmlmfled by the smooth rounded end` land spaced'from vthe walls of 'saidbodyyansll of the terminal. "Thistaperedportion of insulation upon said stem and means forse-'lA the 'bodyisadapted to extend into the `excurlng the' same within the hol-low1metal plosionhamber of the engine, so as to be body, aclosure fortheouter extremityjof completely sweptby the iame of the exthe stem, andafterminal wlre secured`adi1- plosion, and hence cleaned thereby 4of,soot justably in sad metal tip. *.115 or, other. foreign'v matter, theshape be- 3. A hollowstem for a spark plug ailinging such` as tofacilitate the cleansing theresulation4 thereon, a -hollow-innerhead ortip of. Anexpansion Ma of the hollow central therefor, provided withnarrow slits vin' its' stem permitso'f still greater rarefaction ofwalls, a terminal wire, secured-in said tip; the gas vin theinnerchamberand increasesand projecting therefrom, a`rnetal 'bodyflfol 120itsA volume when employed. Further importhe plug, aj projectiontherefrom, -a -cij tant advantages in theaccumulation of gas cularterminal therefor adapted tOi-:encirgin'the'in`eigzeliambei-Varefound'inthe beneclesaid wire;saidterminalprovided'fwithrat centfral' orificeandfiwithqlogitainalznamwtjsgthe said metal'rt-ipfbeiiigfspaced..from .f1-25 "saidi body' totorin,allseliaiiberf corrinnir iic'at ing with theopenings-inf-said tip.and'feircu' tral orifice and with marginal narrow slits,

and with a chamber communicating therewith,a terminal Wire located insaid central orifice, a hollow stem in which said Wire is adjustablysupported, and an insulation for said central stein.

A5. In a chambered spark plug, in combination, a metal cha-mbered body,and a central chambered stem therein, an insulation for said centralstem, a terminal Wire slidingly mounted in said chambered stem, acircular outer ,terminal for said metal body having a central orificeand slits in its Walls communr eating with the chamber in the metalbody, the chambers in said stem and body being in communication witheach other.

G. The combination with a chambered metal body of a circular terminaltherefor, provided With a central oriic'eand'with narrow longitudinalslits in itswalls, the said oriiice and slits communicating with saidchamber and With each other the edges of said central orifice beingexternally counter- .sunk substantially as described.

"4'. In combination in a spark plug, a chambered bodyand a chamberedinner stem therefor, an insulation separating-said body and stein, a tipfor said chambered stem provided With narrow openings communicatinglwith the chamber in the body, a terminal for the body provided .With aVcentral opening and with narrow slits communicating with in saidcentral oriice.

In testinionyvwhereof, We hereunto set our hands this'th day of December1908.

' JOHN SHARP.

VILLAM SHARP In presence of* WM. M. Momma, GEO. S. COLE.

eoV

the chamber in-said body, and a terminal for

